In this paper I try to explain why Lakatos’s (and Popper’s) conventionalist view must be replaced by a phenomenological conception of the empirical basis; for only in this way can one make sense of the theses that the hard core of an RP (Research Programme) can be shielded against refutations; that this metaphysical hard core can be turned into a set of guidelines or, alternatively, into a set of heuristic metaprinciples governing the development of an RP; and that a distinction can legitimately be made between novel predictions and facts to which a theory might have been adjusted post hoc. Two basic metaprinciples are finally examined: the (conservative) Correspondence Principle and various (revolutionary) symmetry requirements; both of these heuristic devices illustrate the fundamental role which, according to Lakatos, mathematics plays in the progress of empirical science.

Dynamic interaction is said to occur when two significanrly different fields A and B come into relation, and their interaction is dynamic in the sense that at first the flow of ideas is principally from A to B, but later ideas from B come to influence A. Two examples are given of dynamic interactions with the philosophy of mathematics. The first is with philosophy of scicnce, and thc sccond with computer science. Theanalysis cnables Lakatos to be charactcrised as thc first to devclop the philosophy of mathematics using ideas taken from thc philosophy of science.

Imre Lakatos’ idea that history of science without philosophy of science is blind may still be given a plausible interpretation today, even though his theory of the methodology of scientific research programmes has been rejected. The latter theory captures neither rationality in science nor the sense in which history must be told in a rational fashion. Nonetheless, Lakatos was right in insisting that the discipline of history consists of written rational reconstructions. In this paper, we will examine possible ways to cash out different, philosophically interesting, relationships: between rationality and science, between rationality and philosophy of science and/or epistemology, and, of course, between history and philosophy of science. Our conclusion is that the historian of science may be a philosopher of science as weIl, but if that philosophy of science is essentially a historical and dogmatic, it either cannot be used for history or it will deprive history of some of its most interesting and useful categories.

Imre Lakatos argued that a theory of scientific method must be empirical, and therefore self-applicable; the standards it imposes on scientific theories must be ones it satisfies itself. But in relying on this standard of self-referential consistency to protect his theory from criticism, Lakatos becomcs vulnerable to relativism. He escapes by hypothesizing that scientific changes which are methodologically progressive according to his theory are also progressive epistemically. The question is whethcr his theory of method has the resources to warrant this hypothesis. I construct a line of argument logically open to him, and use its inevitable failure to show that his epistemic aspirations depend on precepts of method that he has wrongly rejected.

Lakatos’s approach to prediction and novel facts is of considerable interest. Prediction appears in his conception in at least three different levels: a) as an important aim of the research programs; b) as a procedure -a key method- for increasing our scientific knowledge both theoretically and empirically; and c) as the way to assess the scientific character of knowledge claims -means for evaluating results-. At all these levels he envisions a close connection between prediction and novel facts. The paper has four aims. First, to examine his concept of “prediction” in Lakatos’s MSRP, taking into account different aspects (semantical, logical, epistemological, methodological and axiological). Second, to clarify the notion of “novel facts”, which requires the consideration of the various ways in which new facts can be understood. Third, to examine the prediction of novel facts as criterion of appraisal (theoretical, empirical and heuristical). Fourth, to explore Lakatos’s approach (i.e., the concept of prediction linked to novel facts) in connection with the field of economics, in order to shed new light on issues that have been discussed in recent years.

Este trabajo tiene por objetivo examinar la idea de deducción metamatemática en el programa de Hilbert, mostrando su dependencia de conceptos gnoseológicos, tales como el de conocimiento intuitivo. También se comparará esta concepcion de la deducción con la fundamentación intuicionista de la logica. Sostendré que esta deducción metamatemática lleva a una caracterización de la logica como una teoría de las deducciones formales en un sentido particular.This paper aims to examine the idea of metamathematical deduction in Hilbert’s program showing its dependence of epistemological notions, such as intuitive knowledge. This conception of deduction will be also compared with the intuitionistic foundation of logic. I will argue that this metamathematical deduction leads to a characterization of logic as a theory of formal deductions in a particular sense.

Este trabajo se encuadra dentro de una nueva visión de la lógica de Leibniz, la cual pretende mostrar que sus escritos fueron ricos no solamente en proyectos ambiciosos (Característica Universal, Combinatoria, Mathesis) sino también en desarrollos lógico-matematicos concretos. Se demuestra que su “Caracteristica Numerica” que asigna pares de números a las proposiciones categóricas es una semántiea para la cual la silogística aristotélica es correcta y completa, y que el sistema algebraico presentado en Fundamentos de un Cálculo Lógico es una lógica algebraica similar a la de Boole.This work is a contribution to a new view of Leibniz’s logic, pretending to show that his writings were not only rich in projects (Characteristica, Combinatoria, Mathesis), but also in concrete logico-mathematical developments. We prove that his “Numerical Characteristic” assigning pairs of numbers to terms of categorical propositions, is a complete and correct semantics for aristotelian syllogistic, and the algebraic system presented in Fundamentals of Logical Calculus is essentially a complete version of boolean algebraic logic.

EI desarrollo de su teoría de las leyes como relaciones entre universales condujo a Armstrong a establecer un marco metafísico general mas complejo que el que sus anteriores trabajos presentaban. En este artículo se exponen los aspectos principales de la metafísica de particulares y universales exigida por la identificación original de Armstrong de las leyes con estados de cosas universales. Además, se presentan diversas dificultades que pueden hallarse en su propuesta, y algunas soluciones para las mismas. Los temas principales que se discuten son las leyes con excepciones, las leyes con restriccionesespacio-temporales, las leyes probabilísticas y las leyes no ejemplificadas.The development of his theory of laws as relations between universals led Armstrong to set up a more complex general metaphysical framework than that advanced in his previous works. In this paper I present the main traits of the metaphysics of properties and particulars required by Armstrongsoriginal identification of laws with universal states of affairs. Besides, I advance some serious drawbacks that can be found in his proposal and I also offer some solutions to them. The main subjects to be discussed here will be laws with exceptions, laws with spatio-temporal limitations, probabilistic laws and uninstantiated laws.